Interpretation:
Propose the mechanism for the formation of
Concept introduction:
In the Merrifield solid-phase method, peptide synthesis is carried out with the growing amino acid chain covalently bonded to small beads of a
SN2 reaction is a type of reaction mechanism in which one bond is broken and one bond is formed simultaneously. In first step nucleophilic substitution reaction takes place. Since two reacting species are involved in the slow (rate-determining) step, this leads to the term substitution nucleophilic (bi-molecular) or SN2.
Want to see the full answer?
Check out a sample textbook solutionChapter 31 Solutions
Organic Chemistry
- The chloromethylated polystyrene resin used for Merrifield solidphase peptide synthesis is prepared by treatment of polystyrene with chloromethyl methyl ether and a Lewis acid catalyst. Propose a mechanism for the reaction.arrow_forwardThe structure of limonene appears in Problem 25-13. Predict the products formed when limonene reacts with the followingreagents.(a) excess HBr (b) excess HBr, peroxides (c) excess Br2 in CCl4(d) ozone, followed by dimethyl sulfide (e) warm, concentrated KMnO4 (f) BH3 # THF, followed bybasic H2O2arrow_forwardOne of the steps in the biosynthesis of uridine monophosphate is the reaction of aspartate with carbamoyl phosphate to give carbamoyl aspartate followed by cyclization to form dihydroorotate. Propose mechanisms for both steps.arrow_forward
- Polycarbonates (Section 29.5C) are also formed by using a nucleophilic aromatic substitution route (Section 22.3B) involving aromatic difluoro monomers and carbonate ion. Propose a mechanism for this reaction.arrow_forwardThe polyurethane foam used for home insulation uses methane-diphenyldiisocyanate (MDI) as monomer. The MDI is prepared by acid-catalyzed reaction of aniline with formaldehyde, followed by treatment with phosgene, COCl2. Propose mechanisms for both steps.arrow_forwardNaturally occurring compounds called cyanogenic glycosides, such as lotaustralin, release hydrogen cyanide, HCN, when treated with aqueous acid. The reaction occurs by hydrolysis of the acetal linkage to form a cyanohydrin, which then expels HCN and gives a carbonyl compound. (a) Show the mechanism of the acetal hydrolysis and the structure of the cyanohydrin that results. (b) Propose a mechanism for the loss of HCN, and show the structure of the carbonyl compound that forms.arrow_forward
- Show how the synthetic scheme developed in Problem 23.67 can be modified to synthesize this triiodobenzoic acid X-ray contrast agent.arrow_forwardThe formation of Br2 from NBS first involves the reaction of NBS with HBr to form an iminol intermediate and molecular bromine. The intermediate then undergoes acid-catalyzed tautomerism to form succinimide, the byproduct of the reaction. Propose a curved-arrow mechanism for the conversion of NBS into succinimide that also accounts for the formation of Br2.arrow_forward-Amino acids can be prepared by the Strecker synthesis, a two-step process in which an aldehyde is treated with ammonium cyanide followed by hydrolysis of the amino nitrile intermediate with aqueous acid. Propose a mechanism for the reaction.arrow_forward
- How do you synthesize the amino acid Phenylalanine from benzaldehyde as the starting compound? >please write out all the steps and reagents involvedarrow_forwardThe polymer shown below is synthesized by hydroxide ion-promoted hydrolysis of a copolymer of para-nitrophenyl methacrylate and acrylate. a. Propose a mechanism for the formation of the copolymer. b. Explain why hydrolysis of the copolymer to form the polymer occurs much more rapidly than hydrolysis of para-nitrophenyl acetate.arrow_forwardShow the mechanism for the transesterification reaction that recycles poly(ethylene terephthalate) to dimethyl terephthalate and 1,2-ethanediol when the polymer is heated in an acidic solution of methanol.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning